`InputPin` and `OutputPin` traits for GPIO expanders sitting on slow buses

[felipebalbi]

Hi,

Currently, if I have a GPIO expander sitting on a slow bus, such as I2C or SPI, I'm forced into using blocking embedded-hal i2c/spi traits if I were to implement InputPin and OutputPin for that GPIO expander's driver.

How would the community feel about reproducing InputPin and OutputPin as part of embedded-hal-async with async methods similar to how I2c and Spi are treated? That would allow us to use GPIO expanders with async I2c/Spi traits.

[Dirbaio]

so, #649?

[felipebalbi]

so, #649?

Ugh, completely missed that PR. Closing this issue